Method of modeling and simulation of shaped external occulters

摘要

The present invention relates to modeling an external occulter including: providing at least one processor executing program code to implement a simulation system, the program code including: providing an external occulter having a plurality of petals, the occulter being coupled to a telescope; and propagating light from the occulter to a telescope aperture of the telescope by scalar Fresnel propagation, by: obtaining an incident field strength at a predetermined wavelength at an occulter surface; obtaining a field propagation from the occulter to the telescope aperture using a Fresnel integral; modeling a celestial object at differing field angles by shifting a location of a shadow cast by the occulter on the telescope aperture; calculating an intensity of the occulter shadow on the telescope aperture; and applying a telescope aperture mask to a field of the occulter shadow, and propagating the light to a focal plane of the telescope via FFT techniques.

主权项

1. A method of modeling an external occulter, the method comprising:
providing at least one processor executing program code to implement a simulation system, said program code including the steps of:
providing an external occulter having a plurality of petals, said occulter being coupled to a telescope; andpropagating light from said occulter to a telescope aperture of said telescope by scalar Fresnel propagation, by:
obtaining an incident field strength at a predetermined wavelength at an occulter surface;obtaining a field propagation from said occulter to said telescope aperture using a Fresnel integral;modeling a celestial object at differing field angles by shifting a location of a shadow cast by said occulter on said telescope aperture;calculating an intensity of said occulter shadow on said telescope aperture; andapplying a telescope aperture mask to a field of said occulter shadow, and propagating said light to a focal plane of said telescope via fast Fourier transform (FFT) techniques; separating a focal plane of said telescope into a plurality of channels, using beamsplitters; acquiring one or more beam spots from said laser beacons using a coarse acquisition channel of one of said plurality of channels; sensing a lateral location of said occulter using a pupil imaging channel of another of said plurality of channels; and using a fine acquisition channel of another of said plurality of channels, to fine sense said location of said occulter.